07 S550: thermostat

[kevm14]

I should print something yes. I also need to bring in my receipt for the thermostat from Jan actually.

[kevm14]

And they claim it passed the test and they have the printout to prove it. Great. Well that didn't work out the way I had hoped. I'll either wait until it gets worse or just replace it on my own dime.

Picking it up tonight.

[rpaoness]

Are they charging you for diag?

[kevm14]

No he said he wouldn't. And no apparent upsell on the state inspection. Given all possibilities I declare this a positive experience. I guess I should wait until I have the car though....

[kevm14]

The results speak for themselves (could not duplicate customer concern). Also it behaved perfectly on the drive home.

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[kevm14]

And it behaved perfectly on the drive in. I think I observed that weather more in the 50F range triggers it. I don't know what that means or if it's anything more than circumstantial.

[kevm14]

I see the needle move occasionally but nothing that I would call abnormal.

[kevm14]

It was fine going to work again. Turned the A/C on to dehumidify.
On the way home, it was warmer, like low 60s, and I used the A/C again. This time I caught the temp needle drift down to 80C and the oil temp got pulled down to like 183F. It should really be 200+ when driving and even over 210 is not abnormal. So 183 is clearly wrong.

[kevm14]

I have this now.

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[kevm14]

Back on the transmission cooler question, I grabbed a VIN from a random 09 on Auto trader and looked up radiator and transmission cooler parts/diagram. Then I did the same for my 07.

What I don't understand is it seems to show an external transmission cooler for my 07 that looks like the 09, but it's a different P/N and most importantly, I don't seem to have it. I'll have to do some other research to see if anyone else has figured out external transmission cooling on an older W221. For now, here is all the info to compare against.